1. Field of the Invention
The present invention relates generally to a communication system such as a telephone system and, in particular, to an extra communication service system for providing extra services at a set time by correcting for a time differential which may exist among areas of the destinations of the communication.
A conventional extra service, in response to a set time, is available in which, for a message about the connecting work by the operator or the like, a different route than for daytime is registered for an incoming call during a preset nighttime zone when the operator is absent, and thus the message is routed by the network in accordance with the set time.
Other extra services available at a set time include an answer phone service for automatically registering a presence or an absence at a set time, a call forwarding service for transferring or not transferring or changing the destination according to a set time and a service for preventing an incoming call or an outgoing call in accordance with a set time.
A communication network for providing extra services to subscribers in accordance with a set time includes a time table for storing the set time for each extra service required by each subscriber, and provides an extra service based on the time stored in the time table.
A reference time, however, is based on the standard time used in the communication network providing the extra service. An extra service is not provided with a corrected time differential in the case where a subscriber receiving the extra service has moved to a distant area in which there is a time differential from the reference time.
For this reason, a subscriber receiving an extra service according to a set time is required to set the time and register or change the extra service only based on the standard time used by the network providing the service.
With the recent progress of globalization and multiplication of communication services, the barriers and limitations of time, place and destination have been disappearing to such an extent that any one at any place can send a message by telephone or conduct data communication by simple means at any time, at any place and with any person. This simplicity, however, has given rise to the following problems.
In the case where there is a time differential with the area of the other party, the calling party generally rings up the other party taking the current time zone at the receiving end into consideration. When the other party using a mobile unit and a universal number moves to an area of a different time differential, however, the calling party may call the other party without the knowledge of the existence of a different time differential. On the other hand, the communication network provides communication services regardless of the time differential. Especially in the event that the time at the receiving end is midnight, for example, the called party will be annoyed by the ringing. Even in the case where the night time call forwarding service, the answer phone service or the incoming call restriction service is registered, the subscriber is required to set the time in accordance with the standard time of the home communication network of the subscriber. This is very troublesome.
An object of the present invention is to provide an extra communication service system in which the time differential between the standard time of a destination area and the standard time of the home communication network is corrected in the communication network, and the subscriber can enjoy various extra services according to the time based on the standard time of the destination area.
According to one aspect of the invention, there is provided an extra communication service system with a time corrected by a time differential for a communication system providing extra services according to a set time between communication networks using different standard times, comprising means for determining the time differential between a home communication network of the subscriber that has registered the extra service and the destination communication network based on the communication network ID number information exchanged between the home communication network and the destination communication network of the subscriber, means for setting the time in an extra service time table in the subscriber data stored in a home location register of the home communication network, means for producing and holding a time table according to the standard time of the destination communication network corrected based on the time differential with the destination communication network, and means for changing the time table according to the standard time of the destination communication network in response to a time table change request from the destination communication network, wherein the extra service at a set time is provided based on the time table of the destination communication network according to the standard time thereof.
According to a second aspect of the invention, there is provided an extra communication service system with a time corrected by a time differential, wherein the home communication network of the subscriber who has registered the extra service includes means for determining the time differential with the destination communication network, means for producing and holding a time table based on the standard times of the destination communication network with the time differential corrected, and means for transmitting a time table based on the standard time of the destination communication network to the destination communication network.
According to a third aspect of the invention, there is provided an extra communication service system with a time corrected by a time differential, wherein the destination communication network of the subscriber includes means for determining the time differential with the home communication network of the subscriber who has registered the extra service, means for producing and holding a time table based on the standard time of the destination communication network with the time differential corrected, and means for transmitting the time table based on the standard time of the destination communication network with a corrected time differential to the home communication network of the subscriber.
According to a fourth aspect of the invention, there is provided a communication system for providing extra services corresponding to a set time between communication networks using different standard times, comprising:
a general-purpose location register having stored therein an extra service time table in the subscriber data stored in the home location register of the communication network with the time differential corrected to the time based on the international standard time,
wherein each communication network includes means for reading the time table according to the international standard time stored in the general-purpose register, and based on time differential between the standard time used in each communication network and the international standard time, correcting the time set in the time table according to the international standard time to the time based on the standard time used in each communication network, and
wherein each communication network provides the extra services corresponding to the set time based on the time table with the time differential corrected to the standard time of each communication network.
According to a fifth aspect of the invention, there is provided an extra communication service system with a corrected time differential, in which the means for determining the time differential with the destination communication network based on the communication network ID number information described in the first aspect above is replaced with means for receiving the time information from the clock function built in a mobile unit in the destination communication network and determining the time differential with the standard time of the destination communication network based on the time information.
According to a sixth aspect of the invention, there is provided an extra communication service system, in which the destination communication network includes means for determining the time differential from the time information of the clock function built in the mobile unit and transmitting a signal for correcting the time differential of the clock function built in the mobile unit.